Varnish Cache is a web application accelerator also known as a caching HTTP reverse proxy. It is a FREEBSD licensed. Varnish Cache is really, really fast. You install it in front of any server that speaks HTTP and configure it to cache the contents. It typically speeds up delivery with a factor of 300 – 1000x, depending on your architecture. VCL , Varnish Configuration Language, and its flexibility is one of the key-features of Varnish Cache.

Metrics collected by Varnish Integration
– Description
– The amount of time the server has been running.
Backend Busy
– Maximum number of connections to a given backend.
Backend Connection
– Successful connections to a given backend.
Backend Fail
– Failed connections for a given backend.
Backend Recycle
– Backend connections with keep-alive that are returned to the pool of connections.
Backend Retry
– Backend connection retries.
Backend Reuse
– Recycled connections that has were reused.
Backend Too Late
– Backend connections closed because they were idle too long.
Backend Unhealthy
– Backend connections not tried because the backend was unhealthy.
Client Connection
– Client connections.
Client Connection Closed
– Client connections closed.
Client Connection Accepted
– Client connections accepted. (Available in 3.x only.)
Client Connection Drop
– Client connection dropped, no session. (Available in 3.x only.)
Backend Request
– Backend requests.
Cache Hit
– Requests served from the cache.
Cache Hit Pass
– Requests passed to a backend where the decision to pass them found in the cache.
Cache Miss
– Requests fetched from a backend server.
Client Request
– Parseable client requests seen.
Fetch Chunked
– Back end response bodies that were chunked.
Fetch Closed
– Fetch wanted close.
Fetch EOF
– Back end response bodies with EOF.
Fetch Failed
– Back end response fetches that failed.
Fetch HEAD
– Back end HEAD requests.
Fetch Old HTTP
– Number of responses served by backends with http < 1.1
Fetch Zero Length
– Number of responses that have zero length.
– Total VCLs loaded.
VCL Available
– Available VCLs.
VCL Discarded
– Discarded VCLs.
  • Note :

    Nodelizer supports monitoring Varnish 3+.

  1. Edit config.cfg file :

    • Uncomment the lines containing varnishVersion config variables (remove # symbol). Must provide your varnish major version here.

      For ex.: just run

      • $ varnishstat -V

      This is what you’ll see :

      • varnishstat (varnish-4.1.1 revision 66bb824)
      • Copyright …..

      So you just have to provide ‘4‘ only from the First line of the output.

  2. Restart rptmonitor :

    • For deb/rpm package supported Linux distros :

      sudo /etc/init.d/rptmonitor restart
    • For OpenSUSE(11.4+) with systemd :

      sudo systemctl restart rptmonitor.service
    • For other Linux distro, FreeBSD 8+, Mac OS X+ :

      sudo python /usr/local/bin/rptmonitor/ restart